U.S. patent number 4,759,655 [Application Number 07/063,150] was granted by the patent office on 1988-07-26 for terrorist vehicle arresting system.
This patent grant is currently assigned to Flexible Barricades Inc.. Invention is credited to Alexander M. Gorlov.
United States Patent |
4,759,655 |
Gorlov |
July 26, 1988 |
Terrorist vehicle arresting system
Abstract
A terrorist vehicle arresting system includes a crash barrier
positioned at a side of a driveway instead of across the driveway;
a gate across the entranceway which is dislodged by a vehicle
coming through the closed gate; a net pulled out by the dislodged
gate which captures the vehicle; a capstan to pivot a captured
vehicle into the barrier; and cables from the net looped around the
capstan, such that the netted vehicle is swung into the barrier
where it comes to rest blocking the driveway. The impact-force is
therefore redirected from the direction of the driveway, and the
kinetic energy is dissipated upon impact with the offset, rigid
barrier, thereby permitting the gate structure to be made light,
aesthetically attractive, and quickly closed since the gate does
not have to bear any substantial load. In a preferred embodiment,
the crash barrier is positioned in such a location with repect to
the driveway that the stopped vehicle lying in the driveway blocks
further vehicles from continuing down the driveway.
Inventors: |
Gorlov; Alexander M. (Chestnut
Hill, MA) |
Assignee: |
Flexible Barricades Inc.
(Watertown, MA)
|
Family
ID: |
22047262 |
Appl.
No.: |
07/063,150 |
Filed: |
June 16, 1987 |
Current U.S.
Class: |
404/6; 49/34;
49/9 |
Current CPC
Class: |
E01F
13/048 (20130101); E01F 13/06 (20130101); E01F
13/12 (20130101); B61L 29/02 (20130101) |
Current International
Class: |
E01F
13/06 (20060101); E01F 13/04 (20060101); E01F
13/12 (20060101); E01F 13/00 (20060101); E01F
013/00 () |
Field of
Search: |
;404/6,9,10 ;256/1,13.1
;49/9,34,49,141 ;244/11R,11C ;52/174 |
References Cited
[Referenced By]
U.S. Patent Documents
Primary Examiner: Novosad; Stephen J.
Assistant Examiner: Letchford; John F.
Attorney, Agent or Firm: Tendler; Robert K.
Claims
I claim:
1. Apparatus for arresting vehicles progressing down a driveway
through a gateway across said driveway, comprising:
at least two cables;
a net adapted to entrap a vehicle passing through said gateway from
one side thereof, said net having corners, with predetermined pairs
of corners joined together with one of said cables;
a capstan offset to one side of said driveway, the cables joining
predetermined corners of the net being connected to the
capstan;
means for deploying said net around a vehicle as said vehicle
enters said gateway, with said capstan and said cables swinging
said vehicle in a substantially circular path away from its
original direction along said driveway; and,
barrier means positioned to one side of said driveway in said
substantially circular path, whereby the netted vehicle is caused
to crash against said barrier means.
2. The apparatus of claim 1 wherein said net deployment means
includes net storage means and a break-away gate means originally
disposed across said gateway, said gate means having at least a
portion thereof attached a portion of the cables attached to said
net, such that upon impact of a vehicle with said break-away gate
means, said net is carried around said vehicle, having been pulled
out of said net storage means by virtue of the movement of said
break-away gate means.
3. The apparatus of claim 2 wherein said storage means includes
container means to one side of said driveway for containing said
net in a collapsed condition, whereby said net is pulled out of
said container means upon impact of said vehicle with said
break-away gate means.
4. The apparatus of claim 2 wherein said barrier means includes a
reinforced mound of earth.
5. The apparatus of claim 2 wherein said gate means includes a
slideable gate.
6. The apparatus of claim 2 wherein said gate means includes a
swingable gate.
7. The apparatus of claim 2 wherein said gate means includes two
swingable portions joined at the center thereof.
8. The apparatus of claim 2 wherein said gate means includes
moveable parallelograms of light-weight structure.
9. The apparatus of claim 1 wherein said capstan includes collar
means and means for joining said cables to said collar means,
whereby said cables do not slip off of said capstan upon impact of
said vehicle.
10. The apparatus of claim 1 wherein said barrier means is
positioned such that an impacting vehicle, upon impact, blocks said
driveway.
11. The apparatus of claim 1 wherein said cables are fixed to said
capstan to cause a change in length of said cables during vehicular
travel as said cables wrap around said capstan.
Description
FIELD OF INVENTION
This invention relates to a method and apparatus for thwarting
terrorist attempts at unauthorized gate penetration, and more
particularly to a system for arresting vehicles which is capable of
withstanding high impacts while, at the same time, preventing
penetration.
BACKGROUND
In the past there have been various vehicle barriers placed
directly across roadways to prevent vehicle penetration. One of the
difficulties associated with such barriers is that the barrier must
be removeably placeable across a roadway. Thus the barrier must be
massive enough to arrest a vehicle, yet light enough to be removed
for regular vehicular traffic. In order to provide the above
functions light weight barriers have been substituted for massive
barriers but these light weight barriers have required expensive
and somewhat unreliable cable brakes or shock absorbing systems so
that the light weight barrier will not break on impact. Such a
system is illustrated in U.S. Pat. No. 4,576,507, in which a
barrier is released to come down over a gate to attempt to stop a
high-speed vehicle. In this case, the barrier is prevented from
breaking by virtue of expensive and unwieldy hydraulic or
spring-loaded shock absorbers.
By way of further background, in the past, various flexible
railroad crossing gates and highway guard fences such as
illustrated in U.S. Pat. Nos. 1,848,516; 1,848,517; and 3,292,909
have also utilized various types of shock-absorbing mechanisms
which include brakes on drums or other hydraulic and spring-loaded
systems. These are likewise complicated and expensive. Note that
yieldable barriers have been used for traffic and include U.S. Pat.
Nos. 2,295,205 and 1,828,296 which also involve cable and drum-type
braking systems. Flexible impact-barriers are illustrated, for
example, by U.S. Pat. No. 4,645,375 and a device for arresting
airplanes which includes a net that has a shock-absorbing device
including a braking system is illustrated in U.S. Pat. No.
3,013,750. Finally, U.S. Pat. No. 1,748,563 illustrates a flexible
obstruction-device extending across an open driveway to prevent
access by gradually bringing an automobile to a stop at a
right-of-way, street, or other crossing. Means are provided for
retarding the paying out of the cables connected to the obstructing
device which includes a braking mechanism consisting of frictional
plates arranged to retard the paying out of the cable.
SUMMARY OF THE INVENTION
In contradistinction to all of the above methods of arresting a
vehicle traveling along a given direction, in the Subject System, a
vehicle is deflected from its direction of travel through the
utilization of a net which captures the vehicle from the front and
side and swings it along an arc tangent to the center line of the
driveway, thereby redirecting the vehicle such that the kinetic
energy is dispersed, not by any retarding mechanism or the
resilient qualities of the retarding device, but by the utilization
of a pivot in the form of a capstan which is offset from the
driveway, and finally by an impact embankment.
The redirection of the inertial force of the oncoming vehicle
dissipates the kinetic energy and swings the vehicle into a
position where it is made to crash against the embankment,
preferably of relatively soft material reinforced by railroad ties
held together by cables. The enbankment by which the vehicle is
stopped is offset from the driveway, thereby not precluding
entrance for authorized vehicles. However, the barrier is
preferably positioned so as to stop the vehicle such that the
stopped vehicle becomes immeidately itself a barrier to other
follow-along vehicles attempting to pass through the originally
violated gate structure.
In a preferred embodiment, the gate, whether it be raised, lowered,
slid, or swung into position is carried away by the impact of the
oncoming vehicle, with the cables being utilized to connect the net
to the capstan also being anchored to the gate as well as to the
net. In one embodiment, the net is connected to the gate via the
cables going around the capstan, with the net being attached to the
gate and cables with a four-point coupling system. In a preferred
embodiment the net is stored at one side of the driveway in a box
or pillar post container.
The purpose of the gate is to make use of the force of the vehicle
to cause the stored net to be pulled out along the side of the
vehicle as it progresses because the gate is connected to the
leading edge of the net by cables or other means.
During normal operation, the netting utilized to capture the
vehicle is stored in the above-mentioned side pillar post and the
cables utilized to connect the corners of the net together around
the capstan are either in ground-level channels for the lower cable
portions or are carried over the top of the gate for the upper
cable portions so that regular vehicle traffic can be maintained
through the gate when opened. The cables are connected to eyelets
in the corners of the net and also to the gate via four coupling
cables or equivalent clamping devices.
Upon the encroachment of an unauthorized vehicle, the gate is
closed rapidly, with the rapid closure of the gate being made
possible by its light-weight construction since the gate itself is
meant to be detachable upon impact and only provides for a barrier
against human traffic as opposed to vehicular traffic.
Because the cables are coupled to the break-away gate, with the
carrying away of the gate upon impact, the encroaching vehicle
carries with it the forward end of the net which entraps the front
end of the truck, bulldozer, or other vehicle at its front, and
this pulls the rest of the net which encapsulates the side of the
vehicle away from the capstan. This causes the vehicle to be netted
and carried or swung in a circular direction around the capstan
where it is made to crash, or at least stopped against a barrier
which is to one side of the driveway. In one embodiment, the
barrier against which the vehicle is made to stop is positioned
such that the vehicle is stopped so that its remains impede or
block further traffic through the driveway. The preferable material
for the barrier is a soft material, such that debris is not spewn
over the entire area.
In contradistinction of the above-mentioned patents, no crash
barriers are placed across the roadway. Moreover, no braking or
shock-absorbing equipment is necessary, with the kinetic energy of
the vehicle being dissipated by virtue of its swing through an arc
and into a bank or rigid barrier. This makes possible the
utilization of a knotless, braided-nylon netting such as
manufactured by Bridport Gundrey Ltd. of Bridport, Sussex England.
It will be appreciated that the breaking force of nylon ropes used
in such a net is between ten and fifty tons, which braking force is
in effect augmented by virtue of the capstan/cable/net system
described above.
The subject kinetic energy redirection system can be utilized with
a number of break-away gates including two swingable gates each
swung from an opposite pillar post, a sliding gate, or a single
swingable gate. Additionally, any other type of gating structure
which is carried away by the vehicle may be utilized. For instance,
one type gate is in the form of a collapsible parallelogram, which
when in its "down" or "closed" position has interlocking hook and
eye latches which are effective in maintaining the gate together
until such time as the vehicle is trapped by the aforementioned
net/cable/capstan system.
In another embodiment, a specialized sliding gate is used which is
supported by trolleys on an upper channel that also houses the
upper cables. The gate structure is such that the cables do not
move relative to each other with the sliding of the gate. Upon
impact, the sliding gate and its associated cables come out of the
channels and are carried away with the front of the impacting
vehicle.
In one embodiment, the upper and lower corners of the net are
connected by a single cable which loops around the capstan. Thus,
each cable constitutes a single loop connecting an upper and lower
corner of the net. Alternatively any two corners of the net can be
connected together by the single loop. The location of the cables
above and below the gate permits regular traffic flow because the
traffic merely runs over the lower cable portions, whereas the top
cable portions are sufficiently high such that normal vehicular
traffic is accommodated.
In a preferred embodiment, the break-away gate is slightly ahead of
the cables which lie at the surface of the driveway such that upon
impact, one portion of the leading lower cable is behind the wheels
of any oncoming vehicle at impact. This ensures the entrapment of
the vehicle in the net and the swinging of the vehicle to one side
by virtue of the capstan/cable/net combination. The cables may also
be fixed in attachment to the the capstan so as to cause a change
between the upper and lower lengths of these cables during
curvilinear travel of the vehicle as some or all of the cables wrap
around the capstan.
In one embodiment, the capstan is provided with an exceptionally
wide top portion to prevent the cables from slipping off the top.
Alternatively, the capstan may be provided with a ring or collar.
The collar may include eyelets or idlers through which the cables
pass. The collar rotates around the capstan during an impact, with
forces between upper and lower cable being adjustable through the
idlers or through slippage of the cables either around the capstan
or through the eyelets or the collar itself.
In summary, a terrorist vehicle arresting system includes a crash
barrier to one side of a driveway instead of across the driveway; a
gate quickly closed across the entrance way which is dislodged by a
vehicle coming through the closed gate; a net pulled out from a
side storage bin by the dislodged gate which captures the vehicle;
a capstan which serves as a pivot for the captured vehicle; and
cables from the net looped around the capstan, such that the netted
vehicle is swung into the barrier where it comes to rest blocking
the driveway. Thus, the Subject System does not require the energy
absorbing barrier to be positioned across the driveway and provides
for the arrest of the intruding vehicle without cumbersome and
expensive shock-absorbing systems and prevents the spewing forth of
debris over a wide area. In one embodiment top and bottom corners
of the net are coupled together by the cables which go around the
capstan. Alternatively, any pairs of corners of the net may be
coupled together by a cable which goes around the capstan. Note
that the corners of the net are joined together by a border cord or
cable which goes through the net along its periphery. The
net/capstan/barrier system thereby redirects the initial reaction
force by changing the direction of the motion of the vehicle so
that the vehicle is fully arrested by the stationary elasto-rigid
structure without the use of shock absorbers for the cables or
cable brakes. The kinetic energy is thus dissipated upon impact
with the offset, rigid barrier, thereby permitting the gate
structure to be made simple and light, aesthetically attractive,
and quickly moved into a closed position since the gate does not
have to bear any substantial load. Unique, in one embodiment, is
the use of a capstan collar and/or pulleys or idlers for the
instantaneous adjustability of the net's upper and lower cable
lengths. Also, the cables leading to the capstan may be attached to
the collar carried by the capstan so that the cables will not slip
off the capstan. In one embodiment, the net is stored at one side
of the driveway gate and is drawn along side the vehicle from a
storage-bin by the impacted gate when the front of an oncoming
vehicle comes into contact with the gate which is carried away due
to the impact of the vehicle with the gate structure. In another
embodiment, the gate's grill work or net gives way allowing the
frame of the gate to trap the vehicle when the vehicle impacts the
gate, such that the wheels of the vehicle have already passed over
this frame. In a preferred embodiment, the crash barrier is made
soft and is positioned in such a location with respect to the
driveway that the stopped vehicle lying in the driveway blocks
further vehicles from continuing down the driveway. In a still
further embodiment, either the gate is of a collapsed parallelogram
type, or of a sliding type in which the sliding gate and cables
come out of respective upper and lower tracks upon vehicle
impact.
BRIEF DESCRIPTION OF THE DRAWINGS
These and other features of the subject invention will be better
understood in connection with the Detailed Description taken in
conjunction with drawings of which:
FIG. 1A is a diagrammatic illustration of the entrapment of a
vehicle going through a gate by virtue of a side-catching net and
an offset rigid barrier along with an offset capstan which serves
as a captured vehicle pivot;
FIG. 1B is a diagram of the capstan for use in the FIG. 1A system,
illustrating a ring or collar through which the cables of FIG. 1A
pass;
FIG. 1C is a diagrammatic representation of a sliding gate
embodiment showing the attachment of the cables to the net, and a
four-point attachment of the cables in the leading cable loop to
the break-away gate.
FIG. 2 is a diagrammatic illustration of initial impact of a
vehicle with a gate which pulls the net out of a net container;
FIG. 3 is a diagrammatic top view of a vehicle approaching a gate
with the net to one side, also showing the position of the vehicle
after the break away of the gate showing the pull out of the
net;
FIG. 4 is a diagrammatic top view of the swinging of the vehicle
away from the roadway and into an offset barrier;
FIG. 5 is a diagrammatic illustration of a dual gate structure
along with a capstan, illustrating the joinder of the cables to the
net as well as to portions of the gate;
FIG. 6 is a diagrammatic illustration of the gate of FIG. 5
illustrating the opening of the gate to permit normal vehicle
traffic between the upper and lower cables;
FIG. 7 is a diagrammatic illustration of a capstan including a yoke
or collar having eyelets and pulleys, with the various cables going
around the separate pulleys and the yoke functioning to swing
around the capstan body;
FIG. 8 is a top view of the yoke or collar of FIG. 7, showing
eyelets which may be used with or without pulleys;
FIG. 9 is a diagrammatic illustration of one embodiment of a
light-weight, break-away gate, illustrating a light-weight gate
structure which may be easily and quickly raised and lowered, with
interlocking eyelets and rigid hook structures;
FIG. 10 is a diagrammatic illustration of one portion of the rigid
hook and eye structure for use with the gate of FIG. 9;
FIG. 11 is a diagrammatic illustration of the gate of FIG. 9 raised
in its parallelogram form; and,
FIG. 12 is a diagram of a slideable gate which comes out of its
track upon impact by a vehicle.
DETAILED DESCRIPTION
Referring now to FIG. 1A, a vehicle 10 is shown to have passed
through a gateway generally indicated by reference character 12.
Adjacent walls 14 and 16 surround the gateway opening and a
driveway 20 is shown passing through the gateway. As illustrated,
vehicle 10 has broken through the gateway and carries with it a
dislodgeable gate 22 which is normally positioned across the
gateway. Here the direction of travel of the vehicle is illustrated
by arrow 24. As can be seen, gate 22 carries with it a net
generally indicated by reference character 30 to surround a side 32
of vehicle 10, with the net having a leading cable with proportions
34, 34' forming a loop joining a forward or leading upper corner 36
of the net 30 with a forward lower corner 38 of the net. Cable
portions 34 and 34' are shown schematically to be joined to four
corners of the gate via cables 31, 33, 35 and 37. The trailing
portion of the net is secured by a cable having proportions 40, 40'
that form a loop which joins a trailing or aft upper corner 42 of
the net with a trailing or aft lower corner 44 of the net. It will
be appreciated that the cables are looped around a capstan
generally indicated by reference character 50, which has a top
portion 52 and a smooth, thimble-shaped interior barrel or surface
54 about which the cables are adapted to either slip or move with
the rotation of the barrel of the capstan should the barrel be
rotationally mounted to a base. For either the forward loop or the
trailing loop cables, rotation of the capstan will be in the same
direction to tighten the net about the vehicle. In general this
means that the cable portion lengths will self-adjust to pull the
top of the net over the vehicle. Slippage or self-adjustment
between the top and bottom cable portions is important to balance
the forces between the bottom and the top of the net. This
automatically adjusts looseness between the top and bottom of the
net. This is most readily accomplished by the idlers of the FIG. 7
embodiment. Note, in FIG. 1B cable portions 34, 34' and 40, 41' are
coupled to capstan 50 via a ring or collar 51, with the slippage of
these cables through the ring providing for the above cable length
adjustment. The collar itself provides for pivoting about a
vertical axis of the capstan.
Referring now to FIG. 1C, net 30 may be housed in folded form as
illustrated, in which the leading eyelets 36 and 38 are joined by
cable 34, 34' which forms a loop through ring 51 of capstan 50. It
will be appreciated that sliding gate 22 includes trolleys 55 which
roll along an upper channel (not shown in this figure) with the
gate frame being attached to cable 34 via an eyelet 57 carried by
trolley 55 and via an eyelet 59 carried by cable 34 which goes
around a transverse bar 61 of the frame of gate 22. This in essence
connects eyelet 36 of net 30 with the top portion of the break-away
gate.
With respect to eyelet 38, this is connected via cable portion 34'
to an eyelet 63 carried by a bottom portion of the frame of gate 22
and by an eyelet 65 which is carried on cable portion 34' and
surrounds a transverse lower bar 67 of gate 22. This eyelet and
trolley construction permits the sliding of gate 22 in the
direction of double-ended arrow 69 without the removal of net 30
from its stored position as illustrated.
Upon impact with a vehicle, however, the break-away gate pulls out
of its respective tracks as illustrated in FIG. 12 to be described
hereinafter, and pulls forward eyelets 36 and 38 which carry the
leading edge of net 30 about the vehicle which is impacting the
gate. The trailing edge of the net has afore-mentioned eyelets 42
and 44 coupled to cable portions 40 and 40' which again run in a
loop through ring 51 on capstan 50. In this diagram it can be seen
that the forward or leading edge of the net is coupled in a
four-point connection system to the break-away gate via cable 34,
34', thereby establishing the four-point linkage system described
in connection with FIG. 1A.
It will be noted that the net is generally rectangular in
configuration, having upper and lower corners joined by cable
portions 34, 34'; or cable portions 40, 40' respectively. This
rectangular configuration constitutes a preferred embodiment, with
other net configurations being within the scope of this
invention.
In operation, and referring back to FIG. 1A, the vehicle 10 impacts
gate 22 which causes net 30 to surround the vehicle as shown, with
the net being pulled out of a storage container generally indicated
at 56 by virtue of its being attached via cables to the gate
carried away by an impacting vehicle. By virtue of the capstan and
the netting, which can be a knotless net such as mentioned
hereinbefore, the vehicle is swung in a circle illustrated by
dotted line 60, such that the momentum of the vehicle initially
along the center line of the driveway is now moved off axis as
illustrated by arrow 62, such that the vehicle comes to rest
against a barrier 64 which is to one side of the roadway, thereby
dissipating the kinetic energy associated with the vehicle. Note
the barrier face is preferably perpendicular to circle 60 for
maximum effect. In one embodiment, barrier 64 is located adjacent
the roadway so that the vehicle is stopped across the roadway,
thereby preventing any further traffic through the gateway.
Alternatively, the vehicle may be swung a whole 180 degrees around
to wall 14 where it is allowed to smash up against the wall or some
other barrier in a zone generally indicated by dotted line 66 which
forms a debris disposal zone.
Note in one embodiment in which Kevlar cables are used, each
portion of a cable loop is capable of withstanding 110,000 pounds
of force. This translates into a total tensile strength of 440,000
pounds.
As can be seen, the operation of the system is such that upon
impact, the gate becomes dislodged carrying the light-weight net
which is stored to one side or the other of the gateway such that
the net both captures the vehicle and swings it away from the
driveway by virtue of the cables going around capstan 50. This
changes the momentum by changing its direction, whereby all the
force is dissipated upon impact with the barrier. It will be
appreciated that the reason for the utilization of a net and
capstan is to effectuate a momentum direction change which
alleviates the problem of having hydraulic cylinders for net
cables, or complicated braking mechanisms for the cables. It will
be appreciated that barrier 64 can be a mound of earth surrounded
by a cofferdam along with reinforcing railroad ties and cables such
that the impact is softened, thereby to minimize the amount of
debris thrown off.
Referring now to FIG. 2, vehicle 10 is illustrated as having
impinged upon gate 22, with gate 22 having been carried away from
wall 14. Thence the vehicle proceeds to be pivoted about capstan 50
into barrier 64 which is to one side of driveway 20. In this case
it can be seen that the upper cable portion 34, is lifted above the
top of the vehicle 10 and pulls out the top of net 30 so as to
encompass the top portion of vehicle 10. Simultaneously the lower
cable portion 34' having been held in a channel in the driveway and
at least its forward end having been run over by vehicle 10 pulls
out the bottom of net 30 from container 56.
With the barrier just to one side of the driveway, the final
position of vehicle 10 as illustrated in dotted outline 10' is such
that it blocks driveway 20 and prevents any further vehicular
traffic.
How this is accomplished is illustrated in FIG. 3 in which the
lower cable portions 34', 40' are shown in channels in driveway 20.
Here net 30 is held in container 56 in wall 16, with capstan 50
being on an opposite side of the driveway adjacent wall 14. As can
be seen, lower cable portion 34' is anchored to gate 22 at points
68 and 70, whereas this cable is fixed to the lower leading corner
of net 30 at point 72 adjacent point 70. The other end of this
cable is joined to the upper leading corner of the net at point 74.
As the vehicle 10 proceeds to crash through gate 22, and as
illustrated at dotted line 80, break-away gate 22 is bent around at
least a right front portion of the vehicle here illustrated at 82.
At this juncture, net 30 has been pulled out of its container 56 as
illustrated by dotted line 84 so that it begins to surround the
front portion and the left side of the vehicle, when vehicle 10 is
in position 80.
Referring now to FIG. 4 net 30 surrounds the vehicle as the vehicle
impacts barrier 64, with the barrier in this case having a face 85
tangent to a circular path 86 along which the vehicle is swung.
Here barrier 64 is close enough to the driveway that the vehicle
comes to rest blocking the roadway. In this illustration cable
portions 34, 34' and 40, 40' are connected to the respective top
and bottom corners of the net as illustrated. Note, the maximum
penetration is shown by arrow 87 and can be limited by moving the
capstan closer to the roadway and shortening the respective
cables.
Referring now to FIG. 5, in one embodiment gate 22 may be a
double-gate, light-weight, swingable structure having swingable
gate portions 90 and 92 locked together by a latch 94, with the
gate being hinged to walls 14 and 16 at breakable joints 96 mounted
to upstanding pillars 98. Here it can be seen that net 30 is
carried to one side of the gateway in container 56, with the bottom
cable having its lower portion 34' within a channel 100 within
driveway 20 where it is anchored at point 102 to gate 22 and also
to the leading bottom corner of net 30. This cable may also be
attached to the left hand side of the gate at a point 104 such that
when the gate is dislodged, cable portion 34' pulls the bottom of
net 30 out of its container. Here it can be seen that the upper
leading cable portion 34 is carried above gate 22, whereas the aft
upper portion 40 is also carried above the walls 14 and 16 as
indicated.
Referring to FIG. 6, with gates 92 open, a vehicle may proceed
through the gate structure, with cable portions 34 and 40 being
above any vehicle which is moving down the driveway, whereas cable
portions 34' and 40' are located in channels 100 and 100'
respectively which are embedded in driveway 20. In this
illustration, net 30 is shown in a folded position to the left of
the driveway.
It will be appreciated that gate portions 92 need not be of a very
heavy nature so that they can be closed quickly and locked via
latch 94, assuming enough advanced warning for an approaching
vehicle. It is the purpose of the subject net-catching structure
and momentum change capstan that any gate structure may be made so
light that it can be closed extremely rapidly as opposed to the
heavy gate structures which were thought to be necessary. The heavy
gate structures were necessitated, it was thought, because of the
mass of vehicles involved which would seek to penetrate the gate
structure.
Referring now to FIG. 7 the capstan 50 may as usual include a
thimble like shape with the aforementioned top 52 and a smooth
inner surface 54 about which the aforementioned cables may pass.
The capstan in this Figure is shown to have a base portion 106 and
includes in this embodiment ring 51 as a collar generally
illustrated by reference character 110 which surrounds surface 54
and contains two eyelets 112 and 114 to which pulleys 116 and 118
are attached. Through these pulleys pass cables 34, 34' and 40,
40', with the pulleys serving to provide for movement of the cables
back and forth around the pulleys to adjust changes in the length
of the upper and lower cable portions between the top and bottom of
the net, whereas collar 110 serves the purpose of retaining the
cables about the capstan since collar 110 cannot slip off past
capstan head 52.
Referring to FIG. 8 collar 110 may be of a jointed configuration as
illustrated by bolt and pivot point 120, with the collar being
clamped at its ends 122 and 124 with suitable bolting means around
the capstan. Here eyelets 112 and 114 may be of such rigid
structure and of such smoothness that the cables may pass through
eyelets 112 and 114 without the aid of pulleys 116 and 118 of FIG.
7.
It will be appreciated that the purpose of collar 110 is to prevent
cables from slipping out over the top of capstan during a high
impact collision, with the collar being sufficiently strong to
prevent the cables from breaking away from the capstan.
Referring now to FIG. 9 in one embodiment, the gate structure 22
may take on a flexible parallelogram configuration with vertically
rising members 130 hingedly attached at points 132 and 134 to
respective interconnect members 136 and 138. The outer portion of
gate 140 is hingedly attached to an upright stancion 141 at points
144 and to an inner upstanding member 148, again at points 144.
Here the two sides of the gate are joined together by a hook 150
engaging an eyelet 152 with the hook being secured to upstanding
member 148 and with the corresponding eyelet being rigidly attached
to upstanding member 154 of the opposing gate structure, such that
when the gates are lowered, the hook and eyes are engaged thereby
to prevent the opening of the gate. They are also of sufficient
numbers so as to prevent an impacting vehicle from bursting the
gate structure and thereby avoiding the net. The hook and eye
structure is illustrated in FIG. 10 in which hook 150 is
illustrated as having an inwardly turned end 151 within eyelet 152,
portions of the upstanding members 148 and 154 being as
illustrated.
Referring now to FIG. 11, gate portions 160 and 162 are shown in
their uplifted position, in which the gates with their upstanding
members 130 and their now angled interconnect members 136 and 138
occupying the position shown to permit passage of vehicular traffic
through the gateway. It will be noted that members 136 and 138 are
pivoted at points 144 on their respective stancions 141, with hooks
150 downwardly projecting as illustrated so as to be able to
communicate with corresponding eyelets 152 in gate 162.
Referring now to FIG. 12, for sliding gates, the cables are
contained in upper and lower channels and do not move relative to
each other during the sliding of the gates. Here gate 22 may be of
a sliding structure such as illustrated at 170, in which the
sliding gate is translatable as indicated by double ended arrow
172, with the gate being supported from the top via channel 174 on
which roller assemblies 176 roll on a flange 178 thereof. The gate
is which that upon impact from the direction of arrow 180, the gate
carries in the direction of arrow 180 such that the rollers and the
cables come out of channel 174 which is opened rearwardly. This
carries the upper cable portions 34 and 40 in the direction of
arrow 182, it being understood that cable portion 40 is coupled to
the gate structure 170 via a fixed link 184 which has at its other
end an eyelet 186 which surrounds a round bar 188 on gate structure
170, such that the gate may move in the direction of double ended
arrow 172, with bar 188 moving in the direction of double ended
arrow 190 without moving cable portion 34 or 40.
This is likewise the case for the bottom of gate 170 which has a
bar 192, with links 194 and 196 surrounding cable 34' and bar 192
simultaneously. Link 196 is joined to bar 192 at point 200, whereas
link 194 is joined to cable 34' at point 202. It will be
appreciated that cable portions 34' and 40' are carried in channels
204 and 206 which are within driveway 20.
Upon impact of a vehicle in the direction of arrow 180, the cables
jump out of their respective channels along with gate 170 so as to
carry the appropriate cables and the net with the gate.
This provides for a slideable gate assembly, in which the gate may
be slid backwards and forwards without moving the respective cables
but, which carries the cables with it when the gate is forced
rearwardly by virtue of impact with a vehicle, thereby to pull the
net previously described out of its container.
Having above indicated a preferred embodiment of the present
invention, it will occur to those skilled in the art that
modifications and alternatives can be practiced within the spirit
of the invention. It is accordingly intended to define the scope of
the invention only as indicated in the following claims.
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